Now for your particular case, Tumblr uses some HTML5 & JavaScript constructs that are not supported in WebView and hence you are not able to see what is there in that aside tag (Anonymous asked etc.) which gets loaded after page has loaded, probably
via JavaScript.

If you open URL "http://html5test.com/" in WebView on Windows 8.1 Enterprise Edition, HTML5 score is 325. In regular IE i.e. Desktop version as well as Modern UI version this score is 376.

Finally I will quote what Matt has mentioned in his Blog

The WebView control is intended to allow a Store app developer to embed some part of the web inside the application, but should not be added to an application to allow browsing to any site on the Internet - it should be used to link specifically to pages
hosted on your own website for the purposes of being displayed within your Store application.

For example: if you have content that you think may change quite often, it could be easier to place this information in a WebView control rather than update your application via the store.

However, what it is not intended to be is a portal from a Store app into a Web app. In fact, your Store app will be rejected from listing in the Store if this is your primary use of the WebView control.

-- Vishal Kaushik --

Please 'Mark as Answer' if my post answers your question and 'Vote as Helpful'
if it helps you. Happy Coding!!!

1. Open this URL in your browser: http://wildstaronline.tumblr.com/post/92288823709/if-a-flock-of-protostar-employees-is-called-an-audit

You see the post that begins with "Anonymous asked:", right?

2. Using my sample code above, just put a WebView control on a XAML page. and then paste that code that navigates to the URL above in some event that gets fired when the page loads or tie it to a button click if you want.

3. Run the app and look at the web page through the WebView.

Do you see the post? Do the web pages look the same? Is the WebView showing all the HTML?

Now for your particular case, Tumblr uses some HTML5 & JavaScript constructs that are not supported in WebView and hence you are not able to see what is there in that aside tag (Anonymous asked etc.) which gets loaded after page has loaded, probably
via JavaScript.

If you open URL "http://html5test.com/" in WebView on Windows 8.1 Enterprise Edition, HTML5 score is 325. In regular IE i.e. Desktop version as well as Modern UI version this score is 376.

Finally I will quote what Matt has mentioned in his Blog

The WebView control is intended to allow a Store app developer to embed some part of the web inside the application, but should not be added to an application to allow browsing to any site on the Internet - it should be used to link specifically to pages
hosted on your own website for the purposes of being displayed within your Store application.

For example: if you have content that you think may change quite often, it could be easier to place this information in a WebView control rather than update your application via the store.

However, what it is not intended to be is a portal from a Store app into a Web app. In fact, your Store app will be rejected from listing in the Store if this is your primary use of the WebView control.

-- Vishal Kaushik --

Please 'Mark as Answer' if my post answers your question and 'Vote as Helpful'
if it helps you. Happy Coding!!!